I picked up this game, it came out roughly a month ago (give or take). It's called Pocket Heroes.
It's an async multiplayer ONLY turn based grid based RPG. It supports up to 4 players in a game. You can have multiple games going on, with different characters. It only costs a buck.
It has its fair share of glitches and all-around jankiness. Items are pretty pricey, but there's IAP for gold. I haven't had to do that, but enemies drop loot and food and gold. The rate increases if more people play in a game. But it's really the first of its kind on iOS, and I hope someone with more dev experience steps up to the plate.
It's only a buck. The devs say they plan on adding more quests and classes, and they have been pretty active on TouchArcade forums. I hope they keep supporting it, but anything can happen.
If you buy it, I'll play with you since I have my iPod with me at work all times.
http://itunes.apple.com/us/app/pocket-heroes/id499929946?mt=8
